Kylo Ren

Rey

Instead of being separated when Starkiller Base was falling apart, the planet itself crumbling to pieces, Rey and Kylo Ren's battle is interrupted, but they remain together. Ren subdues and captures Rey, but is injured in the process. Once he has Rey aboard his ship, on the way to bring her to Snoke as ordered, he undergoes a transformation that cements his connection to the Dark Side of the Force, with his eyes turning completely black and his back sprouting a pair of bony wings. Rey is horrified, but during Ren's transformation, he was able to plant the seed of Darkness in her, which took root and grew, until he was able to convince her to join him, and swear to abandon the Light.

She has doubts at first, but Ren does his best to persuade her she has made the right decision.

Months later, after much training in the Dark Side of the Force, Kylo Ren and Rey have become secret lovers. Rey hatches a plan which will lure Luke Skywalker out of hiding once and for all, though Ren dislikes the plan because it puts Rey in danger. Later, he goes to her, begrudgingly accepting her plan, but before anything can come of it, Rey goes through the same demonic transformation that Ren went through after Starkiller Base. Spurred on by their newly enhanced connection through the Force, they consummate their love.

In an attack on the First Order's new base, Rey and Ren are separated, and Ren is ambushed by Resistance fighters, becoming injured. Rey comes to his aid and they retreat, though he is badly injured.